Re: [PATCH] vfs: new O_NODE open flag

[Jamie Lokier <jamie@shareable.org>]

Andreas Dilger wrote:
> > It's not possible even without this flag. Consider:
> > 
> >         fd1 = open("/tmp/foo",flags);
> >         rc = rename("/tmp/foo","/tmp/bar");
> >         fd2 = open("/tmp/foo",flags);
> > 
> > Or were you asking if *absent that sort of tomfoolery* if it would work?
> 
> No, the point is that we HAVE an fd that points to the original "/tmp/foo"
> opened with O_NODE, and now (after an ioctl, stat, etc) we decide it is
> safe to open the file read and/or write without releasing the existing
> fd.  The whole point is to AVOID this kind of tomfoolery.

Make sense, and openat() seems like a good way to accomplish it.

-- Jamie